UK CARF Dates: 31 Dec 2026, 31 Jan and 31 May 2027
Updated 17 October 2026
General information only, not tax advice. We are not HMRC and are not affiliated with it. Check GOV.UK and your platform. Last checked against GOV.UK: 17 October 2026. Anything marked expected should be re-checked; we plan to re-check the CARF pages on 1 December 2026. Examples use made-up figures or GOV.UK's own examples. Do not enter personal identifiers (National Insurance number, UTR, name, date of birth) on this site.
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Short answer: These are the dates on GOV.UK pages read on 17 October 2026. Weekdays are calendar facts.
| Date | What happens | Source | Weekday |
|---|---|---|---|
| 1 January 2026 | Cryptoasset service providers start collecting user data (the first report covers 1 January to 31 December 2026) | GOV.UK reporting page | Thursday |
| 31 December 2026 | Pre-existing users (at 31 December 2025): the platform has 12 months to collect a valid self-certificate; platforms should obtain them before continuing to transact for pre-existing users | HMRC manual IEIM8000470 | Thursday |
| 31 January 2027 | Platforms must register with HMRC's online service (not live yet) and tell users they will report their details | GOV.UK "Check if you need to report" | Sunday |
| 1 January to 31 May 2027 | Platforms submit their first report | GOV.UK reporting page | 31 May 2027 is a Monday |
| 31 May each year after | Report for the previous calendar year | GOV.UK |
Notes
- The dates for platforms are legal obligations on providers. As a user you are asked for details; the penalty for inaccurate or missing details is up to £300 (more for some non-UK providers).
- GOV.UK doesn't say when each platform will contact you. Don't assume a platform will wait until 31 December.
- We expect many platforms to send requests before the end of 2026; this is not on GOV.UK.
FAQ
Does 31 January 2027 apply to me? It applies to platforms (registration and notifying users).
Where is the penalty explained? Self-certification page.
Calendar file
Download the three dates as an .ics file. It is created in your browser and it is not uploaded.
—31 December 2026 · self-certificate window for pre-existing users
—31 January 2027 · platforms register and tell users
—31 May 2027 · first platform report window ends
Countdowns run to the end of each date in the Europe/London time zone. They are not a personal filing deadline.
What we could not verify
Uncertain. These points were not confirmed on the pages read. A re-check of the GOV.UK CARF pages is planned for 1 December 2026.
- Which platforms will send requests, and when: not stated by GOV.UK. Do not rely on a specific platform's timetable.
- The exact contents of each platform's report beyond "user details and a summary of transactions".
- HMRC's online reporting service for platforms is "not live yet" per GOV.UK on 17 October 2026.
- Staking, airdrops, mining and lending income are now covered in crypto income (HMRC manual and GOV.UK read 17 October 2026). Detailed DeFi cases (CRYPTO61000 onwards) and whether platforms report reward income under CARF: not verified.
- Interaction with EU DAC8 and other countries' rules.
- We plan a re-check of the GOV.UK CARF pages on 1 December 2026.
Sources (official)
- GOV.UK (HMRC), Reporting cryptoasset user and transaction data (last updated 3 June 2026) — https://www.gov.uk/guidance/reporting-cryptoasset-user-and-transaction-data (read 17 October 2026)
- GOV.UK (HMRC), Check if you need to report cryptoasset data to HMRC (last updated 1 January 2026) — https://www.gov.uk/guidance/check-if-youll-need-to-report-cryptoasset-data-to-hmrc (read 17 October 2026)
- GOV.UK (HMRC), IEIM8000470 Self-certificates – time limits — https://www.gov.uk/hmrc-internal-manuals/international-exchange-of-information/ieim8000470 (read 17 October 2026)
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